new poop picture from a failing bird - what could this be

hello all
can anyone out there identify what is keeping this bird from thriving and causing this type of droppings. I looked at the infamous poop page, but really cant see one that matches this.Its my favorite hen, Houdini. I have been giving all the girls, garlic with their food and ACV int heir water for a week or so. I also just bought the grow2max probiotics They eat organic layer feed, with all our organic vegetable scraps. Houdini is now a little slower than she used to be and content to sit still more. Comb might be dropping a little more and she definitely isn't putting on the winter weight yet. We live in Cleveland and last year they were all getting really heavy, which was a good thing since our winter was so bitter cold last year.

There looks to be a lot of mucus and white urates in the droppings. Has she ever had thin shelled eggs or had an egg break inside her? Has she been laying recently? Have you seen any signs of coccidiosis--lethargy, standing puffed up, diarrhea, and poor appetite? I would stop the garlic and ACV today. ACV is not good in hot weather anyway, because it can affect calcium absorption. The garlic may be upsetting something in her gut. Egg yolk peritonitis, coccidiosis, or enteritis might be things to rule out. I would probably give Corid for cocci for 5 days, then if not improved, treat with Gallimycin, Lincomycin, or Bacitracin for enteritis. Here is a link about enteritis:http://www.thepoultrysite.com/diseaseinfo/101/necrotic-enteritis

Thanks for reply.
yes there were some thin shelled eggs, can't really say who is laying them, I thought calcium deficiency, and thought the ACV helped with soft shelled eggs. They have access to oyster shell, but i prefer fresh kale and they have been getting that. She isn't currently laying. She looked puffed up a few times and tired. She seems to be eating when I put out their veggies but she isn't the first to the food like she used to be.
Is the corid you speak of the same that is given to cows (amprolium 9.6% oral solution). I have that I will start that then on to the antibiotics. Not sure where to purchase them since it seems we need a prescription for those
thanks again